Process of smelting sulfid ores.



UNITED STATES PATENT OFFICE.

AUGUST HAGGENMILLER, OF TARICA, PERU.

PROCESS OF SMELTING SULFID ORES.

No Drawing.

To all whom it may concern:

Be it known that I, AUGUST HAGGEN- MILLER, a subject of the German Emperor, residing at Tarica, District of Corongo,

6 Province of Pallasca, and Republic of Peru,

have invented certain new and useful Improvements in Processes of Smelting Sulfid Ores, fully described and represented in the following specification and the accompany- 10 ing drawing, forming a part of the same.

This invention relates to an improved process of smelting pyritic and other sulfid ores in blast furnaces, and the object of the invention is to render the smelting process more eflicient and economical and adaptable to all kinds of sulfid ores, to reduce the amount of the valuable metal retained in the slag, and to increase the amount and improve the quality of the matte or raw metal produced.

The processes heretofore employed for obtaining rich matte or raw metals by smelting raw sulfid ores, and patents heretofore granted relating to such processes, so far as I know, proceed on the principle, more or less modified, of the copper Bessemer process, inasmuch as they transform the crucible of the blast furnace into a kind of converter, or use converterlike vessels as blast furnaces for smelting raw sulfid ores, or propose to do so.

The present smelting process, on the contrary, consists in working raw sulfids in common blast furnaces, from 3 to (3 meters high and of convenient dimensions, using air blasts of high velocity produced by one or more atmospheres over-pressure. In this form, my process represents the complete reverse of the copper Bessemer princlple; for, whereas in the Bessemer process streams of highly compressed air are forced through a bath of molten sulfids, in my process streams of sulficls as they become fused in the smelting zone of the furnace, drop through a bath of air moving at a high velocity resulting from compression. More over, in the Bessemer process the desired degree of oxidation of the sulfids is regulated and limited by the length of time they remain exposed to the effect of the air blast, while in this new process the oxidation is regulated simply by the intensity of the air blast, since with said new process the duration of the exposure of the molten sul- 55 fids to the eff cts of the airb a t s n ar Specification of Letters Patent.

Application filed March 3, 1910.

Patented Mar. 26, 1912.

Serial No. 547,144.

being determined by the height of fall of the molten sulfids.

My new process, which is just the reverse of the Bessemer process, is advantageous in that the blast furnace may be used as such, working continuously, and that when so used it will produce the same or substantially the same result as a converter. With my process the operation is continuous, as distinguished from the discontinuous or separate charge operation of the Bessemer process. All kinds of sulfids whose oxids may be reduced by carbon may be thus smelted by my process, which is not limited in its application to copper only. Another advantage of my process consists in that the heat of oxidation of such metals as can be slagged, iron, for example, may be utilized as smelting heat to such extent that there is no obstacle to the production in one single operation of matte running over or even of raw metals. And not the least ad vantage of my process is that, when charging coal or coke simultaneously with the ore, the oxidation and slugging of metals, iron not excluded, may be limited at will.

An incidental advantage which may be mentioned, is that the high pressure permits of the elimination from the air blast of as much as 90% of its humidity,when compressors for isothermic compression are used. It is well known, that a dry air blast means a saving of heat and consequently an increased output.

In carrying this invention into practice, common blast furnaces, from 3 to 6 meters high and compressors of known construction and of convenient and suitable size may be used. It is of course to be understood that the compressors must be powerful enough to carry the blast, under as high a pressure as may be required in each particular case, to the furnace, into which it enters with a velocity corresponding to the degree of pressure under which it leaves the twyers; and the blast .must be so far as possible equally distributed in the smelting zone. This distribution is an indispensable requisite. From results obtained it is believed that the decomposition of the sulfids as well as the sulfates of the ores results partly from the combustion of the combustible portion of the charge and partly from the energy of the blast; and their constituents oxidize in the se uence of th r exothermic energy and according to the amount of free oxygen present. Therefore the degree of pressure, of one or more atmospheres, required depends on the quantity and the nature of the decomposible sulfids or combinations of sulfids. It-may be supposed for example that with a temperature of 1200 to 1500 centigrade I have, through the heat in the smelting zone of the furnace, about one-half of the required energy of dissociation, while the second half is supplied in the form of mechanical energy by the highly compressed blast.

If the oxidation of the minerals to be treated should generate too much heat, or if the smelting process is impaired by unburnt sulfur of the sulfids, it is advisable to burn off part of the sulfur of the ore by roasting or agglomerating it before charging it in the blast furnace. Insufficient heat in the furnace is supplemented by the addition of raw or coked coal. quantity of air, supplied under as high compression as may be necessary, is regulated by the diameter of the mouth of the twyers. The conduction of the furnace work and the formation of slag takes place in accordance with known principles.

The great difference between all former Copies of this patent may be obtained" for five cents;

The required processes and mine, as described hereinbefore, consists in that, while the former processes are but a variation of, mine is quite the reverse of the principle of the copper converter process, and, because of its being carried out in common blast furnaces, permits of uninterrupted smelting campaigns.

Vhat I claim is:

1. The process of treating pyritic and other sulfid ores, which consists in smelting the ore in a blast furnace with the aid of an air blast of high velocity due to an over: pressure of one or more atmospheres according to the energy of dissociation of the sulfids in the smelting Zone of the furnace.

2. The improvement in the art of smelting pyritic and other sulfid ores, which consists in subjecting the ore in a blast furnace to the action of an air blast of high velocity due to an over-pressure of one or more atmospheres, the process being continuous.

In testimony whereof, I have hereunto set my hand, in the presence of two subscribing witnesses.

AUGUST HAGGE NMILLER.

lVitnesses H. DENKs, SAMUEL NASCONE.

each, by addressing the Commissioner of Patents,

Washington, D. O. 

